The purpose of this study was to identify psychological, sociological and other factors associated immunization and other health outcomes. Mothers were enrolled in the study from three hospitals in the District of Columbia between August 1995 - September 1996. Mothers were interviewed shortly after giving birth. This "baseline" interview included information on sociodemographic characteristics of the mother, father and infant; the mothers medical history; psychosocial features of the family; and maternal knowledge, beliefs and practices surrounding well child care and immunizations and other health care practices. Two "follow-up" interviews were conducted, one when the infant was between three and seven months of age and one when the infant was between seven months and one year of age. A number of questions and topics covered on the baseline interview (e.g., perceived social norms regarding immunization practices) were repeated in the three and seven month interviews. Additionally, outcome data on health care practices, medical visits, and immunizations were collected during these "follow-up" interviews. Information obtained in the three and seven month interviews on immunizations and medical visits was verified via inspection of medical records at the identified provider sites. Recent analyses have focused on infant-parent bed sharing and breast feeding practices. Previous analyses have focused on infant sleep position and immunizations.